Electrical Transport Study of Sodium Metaborate: NaBO2

Abstract

Using a high temperature solid state reaction approach with the carbonate of sodium  metal and B₂O₃ as starting materials, the Sodium metaborate NaBO₂  have been produced. Pressed pellet of this compound, thermoelectric powers (S) and electrical conductivity (σ) is tested in the temperature ranging from the 440K to the melting point. Finding have been presented as plots of log σT Vs T^-1 and log S Vs T^-1. It is noted that at a certain temperature for the solid, σ jumps by a factor of 10 and reaches a value on the order of 3 around 1000K.For this solid S value exhibits an anomaly at the similar temp; this temp. is known as the phase transition temperature (T_P) of the solid. Utilizing a time dependency analysis of dc electrical conductivity, the ionic (σ_i) and electronic (σ_e) components of total conductivity have been assessed. It can be seen that the contribution of σ_i to σ is greater as compared to the 99 percent for the solid over T_P, and that below T_P, although it declines, it still more than 96 percent up to 500K.It has been determined, based on these findings, that this material can be found in two distinct phases. Above the transition point, the phase is superionic, and below the transition point, it is mixed conductor.